15. Tanks, vessels and pumping
equipment used exclusively for the storage or dispensing of fresh
commercial or pure grades of sulfuric acid with an acid strength of
99% or less by weight, phosphoric acid with an acid strength of 99%
or less by weight, or nitric acid with an acid strength of 70% or
less by weight.

16. Ovens used exclusively for the
curing of plastics which are concurrently being vacuum held to a
mold or ovens used exclusively for the softening or annealing of
plastics.

17. Equipment used exclusively for
the dyeing or stripping of textiles.

18. Equipment used exclusively to
mill or grind coatings and molding compounds where all materials
charged are in a paste form.

19. Crucible or pot furnaces with a
brim full capacity of less than 450 cubic inches of any molten
metal.

56. Containers, reservoirs, or tanks
used exclusively for dipping operations for coating objects with
oils, waxes, or greases where no organic solvents, diluents, or
thinners are used; or dipping operations for applying coatings of
natural or synthetic resins which contain no organic solvents.

57. Containers, reservoirs, or tanks
used exclusively for unheated storage of organic materials with
initial boiling point of 300§F or greater.

58. Containers, reservoirs, or tanks
used exclusively for the storage of fuel oils with a gravity of 25
degrees API or lower; or for the storage of lubricating oils.

59. Containers, reservoirs, or tanks
used exclusively for the storage of fuel oils with a gravity of 40
degrees API or lower and having a capacity of 50,000 gallons or
less.

60. Containers, reservoirs, or tanks
with a capacity of 6000 gallons or less used exclusively for the
storage of organic liquids, except gasoline, normally used as
solvents, diluents, or thinners; inks; colorants; paints; lacquers;
enamels; varnishes; liquid resins; or other surface coatings.

62. Containers, reservoirs, or tanks
used exclusively for the storage of asphalt.

63. Storage tanks with a capacity of
less than 25,000 gallons, used exclusively for the storage of
gasoline.

64. Equipment used for transporting
materials on streets or highways, including those highways defined
by Article X, Section 2 of the Constitution of Texas.

65. Equipment used exclusively for
heat treating, soaking, case hardening or surface conditioning of
metal objects, such as carbonizing, cyaniding, nitriding,
carbon-nitriding, siliconizing or diffusion treating when sweet
natural gas or LP gas is used as a fuel.

66. Crucible furnaces, pot furnaces,
or induction furnaces with a capacity of 1000 pounds or less each,
in which no smelting, reduction, sweating, or distilling is
conducted, and from which only the following metals are poured or
held in a molten state:

69. Water and waste water treatment
facilities using only one or any combination of the following
treatment procedures: flocculation, sedimentation, aeration,
activated sludge, trickling filters or stabilization ponds.
Facilities utilizing incineration, volatile carbon compound-water
separation, gas stripping or similar operations are not exempt.

70. Animal feedlots designed to feed
less than 1000 animals, and total expansion of existing feedlots in
operation prior to March 1, 1972 which do not exceed 100% of the
animal capacity as of March 2, 1972.

76. Temporary separators, tanks,
meters, and other fluid handling equipment used for a period not to
exceed thirty (30) days to test the content of a subsurface stratum
believed productive of oil or gas, provided that all emissions to
the atmosphere other than stock tank vapors be flared.

77. Temporary separators, heaters,
flow treaters, meters, storage tanks, and other fluid handling
equipment used for a period not to exceed ninety (90) days to
establish the proper design of a permanent fluid handling facility
for an oil or gas producing property, provided that all emissions
to the atmosphere other than stock tank vapors be flared.

83. Any portable concrete plant that
accomplishes wet batching, dry batching or central mixing where the
batcher or the mixer is of 9 yd3 or less and that
operates according to the following conditions:

The plant remains at a batching site
for 6 months or less.

A bag filter(s) with a maximum
filtering velocity of 3.0 ft/min is installed on the cement
silo.

The cement weigh hopper is vented to
the cement silo or its own bag filter.

The dust emissions at the batch drop
point are controlled by a shroud having ample suction exhaust to
deliver the collected dust to a bag filter.

All in-plant roads are controlled by
either watering, oiling, or paving to prevent fugitive emissions
from truck traffic.

All abatement equipment must be in
good condition and operating properly during plant operations.

Before construction of facility
begins, notification must be given to the appropriate regional
supervisor of the Texas Air Control Board.

84. Any additional cement silo which
will be temporarily located at a batch site and will meet the
following conditions:

The cement silo is equipped with bag
filter(s) having a maximum filtering velocity of 3.0 ft/min.

Transfer of the cement from the
temporary silo is accomplished by an enclosed system.

All abatement equipment is in good
condition and operating properly.

Before construction of the silo
begins, notification must be given to the appropriate regional
supervisor of the Texas Air Control Board.

85. Gas dehydration units outside the
corporate limits of any city processing gas streams containing less
than 100 grains S/100 scf at a rate less than 10 MM scfd.

86. Any portable rock crusher with a
production rate of 400 ton/hr or less that operates according to
the following conditions:

The plant remains at the crushing site
for 6 months or less,

All in-plant haul roads remain in a
wetted condition,

Water sprays are located at all belt
transfer points, shaker screens and inlet-outlet of primary and
secondary crushers,

The plant is located at least 1/2 mile
from any occupied facility or recreational area,

The plant is located at least one mile
outside the nearest corporate limits of any city or town,

The plant is located at least 1000
feet from any state or federal highway, and

Before construction of the facility
begins, notification must be given to the appropriate regional
supervisor of the Texas Air Control Board.

87. A stationary tank, reservoir, or
other container used for the storage of liquid petroleum gas
(L.P.G.), if such tank, reservoir, or other container is a pressure
vessel capable of maintaining working pressures sufficient at all
times to prevent vapor or gas loss to the atmosphere.

88. Any grain storage facility which
satisfies the following conditions:

The storage facility processes only
grain grown by owner(s).

The plant is located at least 1000
feet from any occupied facility or recreational area.

Before construction of the facility
begins, notification must be given to the appropriate regional
supervisor of the Texas Air Control Board.

89. Paint spray booths designed and
operated according to Federal Occupational Safety and Health
Standards and in which no metal based paints are used or metal
spraying or metallizing is done and:

Dry filter media is used to control
paint particulate from intermittent paint spraying and in which the
paint spray rate is no more than three pounds per hour or,

A water wash particulate control
system is used to control paint particulate and the paint spray
rate is no more than eight pounds per hour.

90. Revisions to pilot plants built
prior to March 5, 1972 and revisions to pilot plants which were
exempt from permit requirements when originally built, provided
that operation of the revised facility will satisfy the following
conditions:

1. The facility will operate for the purpose of:

a. Testing the manufacture or market potential of a proposed
product, or
b. Defining the design of a larger plant, or
c. Studying the behavior of an existing plant through modeling in
the pilot plant.

2. The facility will operate in compliance with all
Regulations of the Texas Air Control Board and with Federal
Environmental Protection Agency Regulations governing air
pollution.

91. Any wet sand and gravel plant
that obtains its material from subterranean and subaqueous beds
where the deposits of sand and gravel are consolidated granular
materials resulting from natural disintegration of rock and stone
and whose plant production rate is 500 tons/hr or less and whose
in-plant roads ar adequately controlled by water/chemical
sprinkling and/or oiling and/or paving to prevent fugitive traffic
emissions.

92. Wet batch or central mix concrete
batch plants with a production rate 30 yd3/hr or less
that operate in accordance with the following conditions:

A bag filter with a maximum filtering
velocity of 5 ft/min is installed on the cement silo. This filter
must be in good condition and operating properly during plant
operations.

All in-plant roads are controlled by
either watering, oiling or paving to prevent fugitive emissions
from truck traffic.

The plant remains at the batching site
for 6 months or less.

Before construction of the facility
begins, site approval must be received from the appropriate
Regional Supervisor of the Texas Air Control Board.